Longchengpterus is based on holotype LPM 00023, found at Yuanjiawa near Dapingfanga, a compressed incomplete skeleton and partial skull on a single plate. The posterior part of the skull has been damaged. It is elongated with a length of 262 millimetres. The large skull opening, the fenestra nasantorbitalis, is triangular in form and occupies much of the snout. The teeth in the upper jaw are concentrated in the front part and spaced far apart; their number is uncertain. The lower jaws have been well preserved. They are 220 millimetres long and their symphysis is short. Twelve teeth are present in the dentary. They have a sharp point but are laterally compressed, curving slightly inwards.